The present invention relates in general to handpieces used in dentistry, and in particular to a new and useful handpiece having a chamber for receiving an additive that is dissolved into a stream of water passing along the handpiece.
Dental handpieces have an exceedingly wide application in the practice of dentistry. Handpieces include an elongated housing which is used as a handle by the dental practitioner. A rotor is connected to one end of the housing for receiving a bur, brush, diamond stone, abrasive instrument or other rotary implement for cleaning and drilling dental surfaces. Various handpiece designs include rotors which rotate on the axis of the elongated housing or at a variety of angles to the axis of the elongated housing. Rotors are driven either mechanically by a motor connected to a shaft extending through the housing, or by fluid such as air which spins a turbine formed as part of the rotor.
A supply of water is often provided in a conduit extending through the housing or along the exterior of the housing. The conduit terminates at a nozzle near the rotary implement for irrigation during the dental procedure. Optical fiber bundles are also often provided through the housing. For illumination, the fiber bundle terminates at a light emitting end near the bur or brush. When a pneumatically driven turbine is used to spin the rotor, one or more air lines are provided through the housing which open at jet orifices directed against the turbine. It is conventional to provide an air return opening in the turbine chamber which communicates with the interior of the housing for returning air along the length of the housing. The handpiece housing generally includes a supply end which is remote from the rotor and which is detachably connected to hoses or conduits for supplying air, water, light, electricity or mechanical rotary power, depending on the design of the housing.
One example of a modern dental handpiece can be found in U.S. Pat. No. 4,146,964.
Some modern handpiece designs include swivel connections at the supply end of the housing which permit 360.degree. rotation of the housing with respect to its supply hose.
During a dental procedure, large volumes of mist and aerosol are created by the handpiece. The water spray from the handpiece is agitated by the spinning instrument and is intermixed with suspended body fluids from the patient's mouth which may include saliva and blood. These mists and aerosols represent a potential health hazard since they may carry contagions both to the patient's mouth through the water supply, and from the patient's mouth back into the ambient air as a contaminated aerosol of water, saliva and blood.
No mechanism or technique is currently known for controlling this potentially dangerous source of infection.